body {
  margin: 0;
  padding: 0;
}

#container {
  height: 100vh;
}

.bg {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}

.sun {
  margin: 0;
  padding: 0;
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 600px;
  height: 600px;
  background-color: orange;
  border-radius: 50%;
}

.moon {
  margin: 0;
  padding: 0;
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(calc(-50% + -160px), calc(-50% + -180px));
  width: 600px;
  height: 600px;
  box-shadow: 160px 180px 0 cyan;
  border-radius: 50%;
}

.sea {
  position: absolute;
  bottom: 0;
  width: 100%;
  height: 35%;
  backdrop-filter: blur(100px);
  -webkit-backdrop-filter: blur(100px);
  z-index: 100;
}

.sun,
.moon,
.sun-box,
.moon-box,
.bg {
  transition: all 1s ease-in-out;
}

.sun-box,
.moon-box {
  position: relative;
  overflow: hidden;
}

.light .sun-box {
  height: 100%;
}

.light .moon-box {
  height: 0;
}

.light .bg {
  background-color: #ffeea2;
}

.dark .sun-box {
  height: 0;
}

.dark .moon-box {
  height: 100%;
}

.dark .bg {
  background-color: #040720;
}

.btn-box {
  position: absolute;
  top: 5px;
  left: 5px;
  z-index: 101;
  display: flex;
  flex-direction: row;
}

.btn-box div {
  background: rgba(255, 255, 255, 0.7);
  color: #000;
  width: 90px;
  height: 40px;
  line-height: 40px;
  text-align: center;
  margin: 5px;
  font-size: 14px;
  border-radius: 5px;
  cursor: pointer;
}

.btn-box div:hover {
  background: #fff;
}
